A systematic study of carbon-free oxide-based lining for preventing submerged entry nozzle clogging in continuous casting of rare earth steel

The reaction of carbon-free oxide-based (corundum, spinel, zirconia, and mullite) submerged entry nozzle (SEN) lining with rare earth inclusions and its anti-clogging effects under near working conditions were systematically studied. A variety of lining composite test methods were innovatively used to ensure the consistency of test conditions. The experimental results showed that the mullite (acidic oxide) has strong reactivity with rare earth inclusions, and the spinel (basic oxide) has stable chemical properties and weak reactivity with rare earth inclusions. Because alumina is one of the main reactants of clogging formation, corundum is not suitable for SEN lining. There are less clogs on the surface of zirconia, but it will be exsoluted and unstable. Therefore, solving the problem of zirconia exsolution will greatly strengthen its application in SEN lining.